> Last year I wanted to buy Thinking in Bets (great book, btw). I was feeling impatient, so I looked it up on Barnes and Noble's website, and saw that a store where I was had it in stock.
> I went in to purchase it, and the price in store was a couple bucks higher than the listed price online.
If you looked at in on the web and saw that it was in stock, it also had a “buy online and pick up at X store” button on the results page online, which is both more convenient and avoids the problem you relate (they've had that feature for years, and I just tested and it's still there now.)
The in store price is probably higher because people coming in, going through the stacks and de-merchandising books, asking questions, etc., cost more to service, and would be even more unsustainably unprofitable if online prices, which are for sales that don't have those costs associated were charged (meanwhile, online sales would be uncompetitive if in-store prices were charged.)